Write or print the information correctly. The font should always be clear to read, and in the Goldie Locks size (not too big, not too small). While you would want to include as much as possible on the small sheet of paper, remember if the font is too small you will overly focus on your cheat-sheet thereby increasing your chances of getting caught. Also if it is possible to print-out your cheat sheet, do that. It will reduce the chances of your teacher or professor being able to trace it back to you.